A stylus or a stylus pen is often used as an input device to a digitizer associated with a computer screen, mobile device, graphics tablet, and other devices. With touchscreen devices, a user places a stylus on the surface of the screen to write, draw, or make selections by tapping the stylus on the screen. As such, the stylus is used as a pointing device in addition to a mouse, trackpad, or finger.
There is limited space for circuitry in a stylus, and any functionality should be built with minimal components. Due to the limited room, the stylus is typically powered by a single battery, such as an AAA or AAAA battery, which produce voltage levels of about 1.5V. Communicating with the digitizer is more effective if greater voltage levels can be used for the transmission. Transmissions at higher voltage levels result in a higher, and thus improved, signal-to-noise ratio (“SNR”). However, generating high voltage with a low-voltage battery while maintaining long battery life is challenging due to the restrictions on circuit size, cost, or power.